• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.2
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• pp.238-247
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• 2023

Liquefied petroleum gas (LPG) is an attractive fuel for ships considering its current technology and economic viability. However, safety guidelines for LPG-fueled ships are still under development, and there have been no cases of applying LPG propulsion systems to small and medium-sized ships in Korea. The purpose of this study was to perform an objective risk assessment for the first marine LPG engine system and propose safe operational standards. First, hazard and operability (HAZOP) analysis was used to divide the engine system into five nodes, and 58 hazards were identified. To compensate for the subjectivity of qualitative evaluation using HAZOP analysis, fuzzy set theory was used, and additional risk factors, such as detectability and sensitivity, were included to compare the relative weights of the risk factors using a fuzzy analytical hierarchy process. As a result, among the five risk factors, those with a major impact on risk were determined to be the frequency and severity. Finally, the fuzzy technique for order of preference by similarity to ideal solution (TOPSIS) was applied to select the risk rank more precisely by considering the weights of the risk factors. The risk level was divided into 47 groups, and the major hazard during the operation of the engine system was found through the analysis to be gas leakage during maintenance of the LPG supply line. The technique proposed can be applied to various facilities, such as LPG supply systems, and can be utilized as a standard procedure for risk assessment in developing safety standards for LPG-powered ships.

• Design Convergence Study
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• v.15 no.4
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• pp.45-58
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• 2016

The purpose of this study is to investigate the most effective emoticon type in on-line communication context through analysis decoding(by their interpretation, empathy, reaction) of receiver about emotional message included the various emoticon types. Message types were all 5 - only text message and messages included texticon, graphicon, anicon, and photocon that reflected the transitional process of emoticon. Survey questionnaire that included various emotional situations was developed and utilized to undergraduate students to analyze the differences in their gender and majors. Results are as follow. First, the graphicon, anicon and photocon messages had higher effectiveness than others in the pleasure while the text only message had the highest effectiveness of them in the displeasure. Second, female students responded that the graphicon, anicon and photocon messages were more effective while male students responded that text only message was. Third, between Arts/Physical and Science/Engineering majors had significant differences in some message types, and especially Science/Engineering majors showed higher average than other majors in all of the emoticon types. These results can provide the information to design messages by the emotional situation of sender and gender and major of receiver.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.3
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• pp.383-391
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• 2017

In image processing, image segmentation has been studied by various methods in a long time. Image segmentation is the process of partitioning a digital image into multiple objects and face detection is a typical image segmentation field being used in a variety of applications that identifies human faces in digital images. In this paper, we propose a method for extracting the contours of faces included in images. Using the Viola-Jones algorithm, to do this, we detect the approximate locations of faces from images. But, the Viola-Jones algorithm could detected the approximate location of face not the correct position. In order to extract a more accurate face region from image, we use skin color in this paper. In details, face region would be extracted using the analysis of horizontal and vertical histograms on the skin area. Finally, the face contour is extracted using snake algorithm for the extracted face area. In this paperr, a modified snake energy function is proposed for face contour extraction based snake algorithm proposed by Williams et al.[7]

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.7
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• pp.427-437
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• 2016

This study has the goal of analyzing the techniques and characteristics of urban development, after additionally constructing the high-speed railway in Japan's Kyushu district and building a new railway station to enable the existing traditional stations accommodate with the high-speed railway. Such analysis is made in order to draw the conclusion of its intended (designed) meaning and attributes and to further research on finding an applicable urban development method in the domestic railway station development. The object of this study includes examples of stations renewed within the five years when Shinkansen in the Kyushu district was extended or stations which are in process of development such as Hakata station, Kumamoto station, and Kagoshima-chuo station. From the analysis of this study, the strategies are as follows.; active connecting both geographical location and function of Station, re-establishment of relation with city center and Station, establishment of close linking system for both tourist spot development, methods of Shinkansen line construction and extension a development opposite site of railway, securing the living population from high density & Mixed use development of Station Building.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3A
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• pp.211-219
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• 2010

The design concept of high speed railway bridges is applied to a method for increasing the stiffness of existing bridge structures considering the impact factor by a static load. Generally, the process of structural design would be relied upon an advanced foreign technology. However, the dynamic amplification factor (DAF) and dynamic capacity assessment of high speed railway bridges may be conducted essentially a detailed estimation because the resonance phenomenon is affected by the long length (380 m) and high speed (300 km/h) moving of a high speed railway (Korea Train eXpress: KTX). Therefore, this study will be examined the dynamic capacity of the typical PSC Box Girder high speed railway bridge efficiently, and offered the basic information for the reasonable structural design. For this, the static analysis is conducted considering the load line diagram of KTX based upon existing references. In addition, the KTX moving load is transformed into the time series load considering various analytical variables. The time history analysis is assessed reasonable using the transformed time series load. At that time, analytical variables for calculating the time series load are considered loading node distance, time increment and KTX velocity variation etc. The dynamic capacity of the PSC Box Girder high speed railway bridge is examined based upon the FE analysis result systematically. The structural safety is assessed quantitatively in accordance with the related regulation of the inside and outside of the country.

• Journal of Dental Anesthesia and Pain Medicine
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• v.23 no.4
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• pp.221-228
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• 2023

Background: We assessed the relationship between patient age and remifentanil dosing rate in patients managed under general anesthesia with spontaneous breathing using low-dose remifentanil in sevoflurane. Methods: The participants were patients with an American Society of Anesthesiologists Physical Status of 1 or 2 maintained under general anesthesia with low-dose remifentanil in 1.5-2.0% sevoflurane. The infusion rate of remifentanil was adjusted so that the spontaneous respiratory rate was half the rate prior to the induction of anesthesia, and γ^H (㎍/kg/min) was defined as the infusion rate of remifentanil under stable conditions where the respiratory rate was half the rate prior to the induction of anesthesia for ≥ 15 minutes. The relationship between γ^H and patient age was analyzed statistically by Spearman's correlation analysis. Results: During dental treatment under general anesthesia using low-dose remifentanil in sevoflurane, a significant correlation was detected between γ^H and patient age. The regression line of y = - 0.00079 x + 0.066 (y-axis; γ^H, x-axis; patient's age) was provided. The values of γ^H provide 0.064 ㎍/kg/min at 2 years and 0.0186 ㎍/kg/min at 60 years. Therefore, as age increases, the dosing rate exhibits a declining trend. Furthermore, in the dosing rate of remifentanil when the patient's respiratory rate was reduced by half from the preanesthetic respiratory rate, the dosing rate provided was around 0.88 mL/h in all ages if the remifentanil was diluted as 0.1 mg/mL. EtCO₂ showed 51.0 ± 5.7 mmHg, and SpO₂ was controlled within the normal range by this method. In addition, all dental treatments were performed without major problems, such as awakening and body movement during general anesthesia, and the post-anesthetic recovery process was stable. Conclusion: General anesthesia with spontaneous breathing provides various advantages, and the present method is appropriate for minimally invasive procedures.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5D
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• pp.723-734
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• 2008

In this paper, the problems and betterment plan in operating district units plan are studied by selecting typal case locations based on the types of district units plan of the city of Busan. According to the types, 4 locations of 'type of maintaining preexisting district' and 3 of 'type of managing preexisting district' are selected as case locations, based on a scale and characteristics of each location.In systematical aspects of the case locations, indiscreet upward adjustment of the locations, insignificant participation of the citizens and patternization were recognized as problems. And setting accurate standards for target and range of alteration in line with usage plan of the locations would be necessarily urgent. So through the analysing process of the problems arisen from the case locations I would suggests necessary solutions to improve the effectiveness of the district units plan. And In planning aspects, the similarity between the basic directions and the object, batch-application of the density plan, inadequacy of the usage plan, allocations and patterns of structures, and color planning were recognized to have problematic points. Consequently distinguished specific operating-guidelines would be necessary to achieve the basic directions and the object of district units plan. Furthermore, the building-to-land ratio and floor space index are needed to be exactly calculated through providing accurate and logical standards for appropriate development density of structures.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.4
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• pp.389-394
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• 2023

In recent years, use of machine automation is rising in the industry. Ships also obtain machine condition information from sensor as digital information. However, on ships, crew members regularly surveil the engine room to check the condition of equipment and their information through analog gauges. This is a time-consuming and tedious process and poses safety risks to the crew while on surveillance. To address this, engine room surveillance using an autonomous mobile robot is being actively explored as a solution because it can reduce time, costs, and the safety risks for crew. Analog gauge reading using an autonomous mobile robot requires digitization for the robot to recognize the gauge value. In this study, image processing techniques were applied to achieve this. Analog gauge images were subjected to image preprocessing to remove noise and highlight their features. The center point, indicator point, minimum value and maximum value of the analog gauge were detected through image processing. Through the straight line connecting these points, the angle from the minimum value to the maximum value and the angle from the minimum value to indicator point were obtained. The obtained angle is digitized as the value currently indicated by the analog gauge through a formula. It was confirmed from the experiments that the digitization of the analog gauge using image processing was successful, indicating the equivalent current value shown by the gauge. When applied to surveillance robots, this algorithm can minimize safety risks and time and opportunity costs of crew members for engine room surveillance.

• 한국노년학
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• v.39 no.2
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• pp.261-284
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• 2019

This study examines the vocational adjustment experiences of elderly men who chose a creative occupation after retirement. The aims are to understand the related meanings and to provide specific empirical data on the elderly who hope to start a creative occupation. Five men aged 65 years or older who chose a creative occupation after retirement were enrolled in the study. Data were collected through in-depth interviews with the participants. The collected data were qualitatively analyzed, and a total of 7 categories, 25 subcategories, and 132 concepts were identified. The seven categories were "challenge led by a sense of freedom," "reflection of the need for 'fun,'" "difficulties and limitations felt by a non-expert," "concerns and effort to afford the increasing expenses," "joy for accomplishment," "ways to utilize my creativity," and "reward from increased social participation." The participants felt that adjusting to a creative occupation was a process by which their potential creativity was expressed. They felt the joy of working that they had not felt before, and the series of processes by which they overcame difficulties during work and increased their social participation were in line with the goals of creative aging. In order to help older adults in Korea to choose and adjust to creative occupations in their older adulthood, there is a need for creative-occupation-related education prior to retirement and for various policies and practical efforts that consider the change of social environment. Furthermore, our findings suggest that choosing a creative occupation after retirement is an effective measure for promoting successful aging among the elderly in Korea.

• Korean Journal of Culture and Social Issue
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• v.24 no.4
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• pp.541-562
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• 2018

Conflict of interest (COI) is one of the dominant circumstantial factors of moral corruption across various fields. Several management strategies have been proposed to prevent self-interested decision making in COIs. Among these strategies, message persuasion has been considered as a practical and effective approach. Prior studies have found that framing and repetition are two of the major factors in the persuasion effect of message. However, their effect on moral decision making in COI has not been well explored. The purpose of this study was to compare the differential effects of positively framed message and negatively framed message, and secondly, to investigate how the effectiveness of persuasive message changes through repetitive exposures. A total of 63 participants were randomly assigned to one of 3 framing conditions: positive framing, negative framing, and no-message condition. Prior to the on-line experiment involving a consultation task, differently framed persuasive message were presented to the participants. This process was repeated four times in a row. The results showed that participants with positive-framing message were less likely to provide self-interested consultation than participants in the no-message condition. Also, a U-shaped quadric relation between repetition and self-interest consultation was found. Implications and limitations are further discussed.